## Constant fatigue The [kidneys](https://ul.orna.me/KOge/librarydisease?id=75) play the role of a biological filter. They clean the blood and remove everything extra that is unnecessary from the body. If they do not work well, the blood flow is disturbed, the brain and muscles do not get the necessary amount of oxygen, and toxins accumulate. This makes a person feel tired and weak. ## Sleep problems There is a link between sleep apnea and chronic kidney disease, which can lead to kidney failure over time. Apnea hurts the kidneys because they, like other organs, lack oxygen. ## Itchy skin As toxins build up in your body, they make your skin itchy. In addition, your kidneys are no longer able to maintain the proper balance of minerals and nutrients in your body, leading to bone and skin problems that lead to dryness and itchiness. ## Swelling If the kidneys aren't working well enough, fluid isn't eliminated from the body as it should be, leading to swelling of the face and legs. ## Muscle cramps Kidney problems can cause imbalanced levels of sodium, calcium, potassium, and other electrolytes, which affect muscle and nerve function and lead to cramps. ## Fog in the head Toxin buildup in the body affects brain function, among other things. It causes difficulty concentrating, difficulty gathering thoughts, and forgetfulness. ## Poor appetite and weight loss Kidney disease can cause nausea, vomiting, and loss of appetite, resulting in weight loss. Generally, people think these symptoms are indicative of an issue with the gastrointestinal tract. However, the problem could originate in the kidneys. ## Bad breath Uremia is another condition that results from poor kidney function, which causes bad breath and a metallic taste. ## Change in the color of the urine Protein-overloaded albumin indicates excessive foamy urine; too dark or too light color also indicates excessive foamy urine. But the most alarming signal is blood in the urine. It can be caused by kidney stones, an infection, or a tumor. If you regularly have at least a few of these symptoms, be sure to see a urologist, who will prescribe a series of tests to identify if you have any kidney issues.